The objective of the proposed program is to design and fabricate a prototype 2710 nm (2.71mum) fiber laser for use in myringotomy and middle-ear surgery, and to demonstrate its operation. The 2710 nm wavelength corresponds to a maximum in the absorption spectrum of water, thereby reducing the laser power requirement. Current myringotomy and middle-ear surgery generally involves the use of a scalpel. Some myringotomy and middle-ear procedures utilize CO2 lasers, but these lasers are large, expensive, and operate at a wavelength not optimized for maximum tissue absorption. The primary aim of this project is to make available to the otolaryngology community a new type of fiber laser which is much smaller, less costly, lower power, more flexible, and more reliable than the CO2 laser. The fiber laser system will consist of a 791 nm diode laser pump which is coupled into a double clad, erbium and praseodymium-doped fluorozirconate glass (Er,Pr:ZBLAN) fiber which acts as the 2710 nm fiber laser. Commercially-available components will be selected for this laser. The prototype fiber laser will be evaluated by an otolaryngologist without use of human or animal subjects. The laser will be further optimized, miniaturized, and demonstrated on animal models during Phase II.